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Physcia stellaris var. leptalea (Ach.) Nyl. Syn. I, p. 425. i860. ( Physcia 
hispida (Schreb., F.) of Tuck. Syn. Pt. I. p. 75, pro parte.) 
Thallus white or ashy-glaucous, narrowly divided, the laciniae discrete, 
loosely appressed or subascendent, imbricated; the margins provided with con- 
colorous cilia, below pale. Apothecia blackish or brownish-black pruinose or 
nude, with an entire or slightly crenate margin. Spores 14-25 x 8-1 I/jl. 
Rocks and ledges, Rockland, Camden and No. Haven. In Rockland the 
variation was found growing on a stone wall in the shade of an apple tree. The 
branches of the tree were clothed with P. stellaris. No P. stellaris was found on 
the wall, and no var leptatea elsewhere than immediately beneath the tree. 
Forma albescens (Oliv.) comb. nov. 
Thallus appressed, laciniae narrowly divided, flattened or a little convex, 
discrete but imbricated, white, destitute of marginal fibrils. Without apothecia. 
On rocks in bed of a stream and about its borders. Rockport. The plant is 
much discolored when found in places where it is often submerged. Apothecia 
pruinose in European specimens. Not previously recorded from America. 
Physcia stellaris var. tenella (Scop.) Schaer., Nyl. Syn. I p. 426. i860. 
The variably whitish or ashy-glaucous, laciniae narrowed, ascending, the 
tips hooded and more or less sorediate, marginally white-ciliate. Apoth. small, 
blackish or brownish, more or less pruinose. Spores of the species. 
Common on tree trunks throughout Knox County. 
Forma exempta (Ach.) Th. Fr. Lich. Scand. p. 140, 1871. 
Laciniae shorter and broader then in var. tenella , colored as in the species 
and destitute of marginal cilia in our specimens. 
Maple trunks, Rockport. 
The specimen is remarkable for indicating a close relationship with the 
species, in that one half exhibited the normal development of P. stellaris , the 
other the characters of the form. Many observations have developed the be- 
lief that the var. tenella is a metamorphosis of P. stellaris. 
Physcia lithotea (Ach.) Nyl. Flora 1877, p. 354. 
Thallus appressed, commonly brownish varying toward dark brown and 
glaucous, here and there granulose-furfuraceous, laciniae plane, not discrete, 
subimbricate, beneath black-rhizinose, the rhizoids sometimes showing as a 
dense marginal fringe from above. Apothecia like those of P. obscura, dark 
brown or black. Spores 14-24 x 9-13 /x. 
On stones in a damp situation. Rockland and Warren. 
Commonly without apothecia. The condition sciastra Ach. not yet found. 
Not previously recorded for the United States. 
Physcia lithotodes Nyl. Flora 1875, p. 360. 
Thallus irregularly orbicular, bright green when wet, ashy or greenish- 
fuscous when dry, of short, much dissected imbricate or sub-imbricate laciniae, 
margins ragged, terminations short-digitate or flabelliform, beneath densely black 
rhizinose, the rhizoids showing more or less at the margins. Apothecia entirely 
like those of P. obscura , with an incurved crenulate exciple, or lecanorine, the 
exciple scarcely exceeding the disk, black, with or without fibrils below. Spores 
15-23 x 6-10 m. 
